Answer Posted / raviraj bhardwaj

Primary key - Primary key means main key
def:- A primary key is one which uniquely identifies a row
of a table. this key does not allow null values and also
does not allow duplicate values. for ex,
empno empname salary
1 priya 35000
2 preeti 34000
3 niharika 40000

it will not the values as follows:
1 priya 35000
1 preeti 34000
niharika 35000


unique key~ unique key creates non clustered index by
default.it allows "one null value".

forigen key~
when the primary key of one table injected in other table to
make a relationship then the other key of the other table is
called foreign key.
for ex-
Dept table employs
deptno deptmame deptloc eid ename eadd deptno

in it deptno inter relate bothe the tables so that deptno
works here as a forigen kye..

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Source File: Target EMPNO, SAL Empno, Format 101, 1000 101, 1000 101, 1100 101, 1000, 1100 101, 1000 101, 1000, 1100, 1000 101, 10000 101, 1000, 1100, 1000, 10000 102, 1100 102, 1100 102, 1300 102, 1100, 1300 102, 1200 102, 1100, 1300, 1200 102, 1500 102, 1100, 1300, 1200, 1500 How can i get that output using datastage(ETL) tool

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